from types import TypeType
class Pizza(object):
@staticmethod
def containsIngredient(ingredient):
return False
def getPrice(self):
return 0
class PizzaHamAndMushroom(Pizza):
@staticmethod
def containsIngredient(ingredient):
return ingredient in ["ham", "mushroom"]
def getPrice(self):
return 8.50
class PizzaHawaiian(Pizza):
@staticmethod
def containsIngredient(ingredient):
return ingredient in ["pineapple", "curry"]
def getPrice(self):
return 11.50
class PizzaFactory(object):
@staticmethod
def newPizza(ingredient):
# Walk through all Pizza classes
pizzaClasses = [j for (i,j) in globals().iteritems() if isinstance(j, TypeType) and issubclass(j, Pizza)]
for pizzaClass in pizzaClasses :
if pizzaClass.containsIngredient(ingredient):
return pizzaClass()
#if research was unsuccessful, raise an error
raise ValueError('No pizza containing "%s".' % ingredient)
def main():
myPizza = PizzaFactory().newPizza("ham")
print(myPizza.getPrice())
myPizza2 = PizzaFactory().newPizza("curry")
print(myPizza2.getPrice())
myPizza3 = PizzaFactory().newPizza("beef")
if __name__ == "__main__":
main()
